SDR transceiver having independent mixer and ADC sampling clocks

[Heikki Laamanen]

Hi experts in SDR RF transceivers,

 

I am working on a timing and synchronization system which generates a high-precision timing signal from a terrestrial broadcast signal.  I am looking for a suitable SDR HW-board providing independent clocks for the RF mixers and the ADC.

 

It seems that many SDR boards use transceiver chips having mixer and ADC clocks which are derived from a single clock. Thus, it is not feasible to control the ADC sampling clock frequency without affecting the mixer frequency. For example, some USRP products have Analog Devices AD9361 transceiver chips providing no option to have fully independent mixer and ADC clocks.

 

Why would I like to have independent mixer and ADC sampling clock?

 

The target is to generate a physical clock signal having small jitter and accurate phase. Hence, I need to control the frequency of some VCO based on the information the receiver signal processing gives. The most straightforward way to do this is to control the frequency of a VCO wherefrom the ADC sampling clock is derived.

 

I would appreciate any suggestions about SDR HW-platforms having the capability described above.

 

Regards,

Heikki